RFR: 8341619: C2: remove unused StoreCM node

Tue Oct 8 16:27:00 UTC 2024

On Mon, 7 Oct 2024 11:28:19 GMT, Roberto Castañeda Lozano <rcastanedalo at openjdk.org> wrote:

> This cleanup removes C2's `StoreCM` (store card mark) node and all its special handling code. This node used to model card mark stores in early-expanded G1 post-barriers, and is no longer needed after [JEP 475](https://openjdk.org/jeps/475).
> 
> __Testing:__ tier1-5 (linux-x64, linux-aarch64, windows-x64, macosx-x64, and macosx-aarch64; release and debug mode).

Good.

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Marked as reviewed by kvn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/21385#pullrequestreview-2354992010